Unwinder device for reels of web-like material with temporary accumulator members for the material unwound in the phase of reel substitution and relative method

ABSTRACT

The unwinder device comprises: unwinding members for simultaneously unwinding a first reel (B 1 ) and a second reel (B 2 ), a splicing device ( 151 ) for splicing together a first web-like material (N 1 ) coming from said first reel (B 1 ) and a second web-like material (N 2 ) coming from said second reel (B 2 ), an accumulator member ( 24, 200 ) for accumulating web-like material (N 2 ) supplied from said second reel (B 2 ) before splicing to the web-like material (N 1 ) supplied from said first reel (B 1 ).

TECHNICAL FIELD

This invention concerns an unwinder device for unwinding reels ofweb-like material wound around a central spindle for supplying web-likematerial to a converting or processing line.

The invention also concerns a method for unwinding reels of web-likematerial and for feeding the unwound material to a converting orprocessing line.

STATE OF THE ART

In many industrial applications, there is a requirement to feed aproduction line with a web-like material that is unwound from a reel ormultiple reels in parallel. Typically, the feeding of web-like materialis requested in the paper industry. For example, for the production ofpaper serviettes, rolls of toilet paper, kitchen rolls or the like,converting lines are provided in which a web-like material is suppliedfrom a reel of large diameter and very long axial length to a series ofstations downstream, at the end of which the finished product isobtained. In the case of rolls of toilet paper and similar products, theweb-like material is supplied from one or more large-diameter motherreels and wound onto rolls or logs of smaller diameter, which aresuccessively cut orthogonally to their own axis to obtain the finishedrolls. In certain cases, the web-like material supplied by thelarge-diameter reel or reels is cut longitudinally to form in parallel anumber of rolls of minor height, i.e. of minor axial length.

In the case of serviette production, web-like material is fed from oneor more large-diameter reels that, cut in longitudinal strips ifnecessary, is folded longitudinally, cut, and folded transversely.

The production of rolls, serviettes or other articles is performed athigh speed and in a continuous manner, requiring the periodicsubstitution of the large-diameter reels as they run out. In many case,it is necessary to stop the production line or at least drasticallyreduce the speed thereof, to allow the empty reels to be replaced by newreels. This operation reduces the overall productivity of the line, withevident economic damage. There is therefore a need to provide unwinderdevices that permit a rapid and reliable substitution of empty reelswith new reels. These devices must also handle the splicing, that is thejoining, of the-web-like materials coming from consecutive reels. Thepurpose of this is to obtain a substantial continuity in the supply ofthe web-like material to the downstream production line. The web-likeportion containing the splice is normally discarded. When the lineproduces rolls, the splicing portion will end up on a roll or log thatis subsequently discarded and recycled.

In WO-A-9534497 an unwinder device is describes that permits theautomatic, rapid and reliable splicing of two web-like materials comingrespectively from an empty reel and a new reel in substitution. On thisdevice, a shuttle or carriage is provided that travels between a loadingstation and an unwinding station, each time to transfer a reel from theloading station to the unwinding station and to remove the empty tubularcore from the unwinding zone to an unloading zone. Means are provided onthe shuttle for the preparation and restraint of the free leading edgeof web-like material wound on the reel loaded on the shuttle itself. Inthe unwinding station, a cutting member and a retainer member areprovided that serve to produce a free tail edge on the web-like materialsupplied from the previous supplying reel and to retain this free edgefor subsequently producing the splicing with the free leading edge ofweb-like material on the reel inserted in the unwinding station by theshuttle.

To perform the substitution of the empty reel with a new reel it istherefore necessary to stop the supply of web-like material, even thoughthe splicing operation is rendered particularly rapid by the innovativearrangement of the cutting and splicing means described in thispublication.

In WO-A-0056644 another unwinder device is described that can use thesame type of mechanism for the splicing two web-like materials comingfrom two successive reels. In this case as well, the substitution of thereels takes place after halting the feeding of web-like material to thedownstream production line. Although it is possible to provide a certainaccumulation of web-like material from the unwinder to the productionline, via a festoon accumulator for example, this is not always suitabledue to the characteristics of the web-like material, which may not beparticularly resistant to traction, or due to the high speed of theproduction line, which would require an excessively large accumulator.In addition, the tortuous path defined by the festoon can cause thedetachment of fibres from the web-like material, especially when this ismade of tissue paper, with the consequent production of dust and adiminishment in the characteristics of the finished product.

In EP-A-1136406 an unwinder with a shuttle that transfers the reels fromone or the other of two loading and unloading positions to anintermediate unwinding position is described. The shuttle has amotorized tailstock for unwinding the reel. The substitution of an emptyreel with a new reel requires halting the feed.

Studies have been made for the realization of an unwinder that permitsthe automatic and continuous substitution of the reels, i.e. withouthalting the supply of the web-like material to the converting orproduction line downstream of the unwinder. Examples of unwinders thatshould operate continuously are described in U.S. Pat. No. 5,906,333,U.S. Pat. No. 6,030,496, EP-A-1,270,470, EP-A-0872440 and WO-A-9846509.In these publications, an unwinder is described in which the reel issupported by a pair of oscillating arms in the supply phase. When thereel is nearly empty, the arms deposit it on a cradle formed by tworollers, one of which is motorized, to continue the rotation of the reeland thus the supply of the web-like material. Successively, the pair ofoscillating arms pick up a new reel from a shuttle and starts to unwindthe leading edge with the aid of a suction belt. The free leading edgeof the new reel is made to fall on top of the web-like material beingunwound on the first reel, at this point nearly empty. The contactbetween the two web-like materials should provoke the transport of thefree leading edge of web-like material wound around the second reel andits feeding together with first web-like material until a nip formed bytwo embossing or laminating cylinders is reached, which should splicethe two webs together.

The operation of this unwinder device is extremely insecure as preciselyin the initial, and most critical, phase of feeding the new web-likematerial its transport is entrusted to the simple contact between twoextremely light materials. Nothing guarantees that the web-like materialcoming from the new reel effectively follows the path defined by thefirst web-like material coming from-the reel that is running out. Inaddition, since the splicing of the two layers must occur when they havethe same feed speeds, it is, necessary to arrange the cylinders thatperform the splicing at a considerable distance from the reel unwindingzone. In fact, the amount of web-like material unwound by the new reelin the acceleration phase until the speed reached is the same as that ofthe material coming from the first reel is considerable. The distancebetween the reel and the splicing cylinders must be at least equal tothe length of the web-like material unwound in this phase ofacceleration. The position of the cylinders that perform the splicing ofthe two web-like materials must be situated at the point in which thehead of the second web-like material finds itself at the moment ofsplicing and not further back, because otherwise the head of theweb-like material will remain free and will accidentally wrap itselfaround one of the rollers of the production line with the consequentjamming of the entire production line.

OBJECTS AND SUMMARY OF THE INVENTION

The object of this invention is to provide of an unwinder device thatpermits the substitution of an empty reel with a new reel in a reliablemanner whilst at speed, i.e. by making the new reel rotate at anopportune peripheral speed, typically equal to that of the reel that isrunning out, before performing the splicing of the two web-likematerials.

This, and other objects and advantages, which will appear clear to thoseskilled in the art from reading the text that follows, are essentiallyachieved with an unwinder device including:

-   -   unwinding members for simultaneously unwinding a first reel and        a second reel,    -   a splicing device for splicing together a first web-like        material coming from said first reel and a second web-like        material coming from said second reel,    -   an accumulator member for accumulating web-like material        supplied by said second reel before splicing with the web-like        material supplied by said first reel.

With a device of this type, it is possible to effectively keep undercontrol the free leading edge and the first portion of web-like materialunwound from a new reel destined to substitute the reel that is runningout. The accumulation is carried out until the new reel reaches asuitable rotational speed, which when reached allows the splice betweenthe two web-like materials to be made.

It is no longer necessary, as in known devices, to abandon the free edgeof material coming from the second reel on the material being suppliedfrom the reel that is running out. The possibility of accumulating theweb-like material during the acceleration phase of the second reel alsopermits the splicing device to be situated very close to the position ofthe reels.

In addition, by arranging the temporary accumulator member downstream ofthe zone in which the splice starts between the web-like materialscoming from the two different reels, it is possible to place thesplicing device close to the unwinder, with consequent advantagesregarding the size of the line and reliability in controlling thematerial in transit.

In a practical and advantageous embodiment, the accumulator member isreversible, i.e. realized in a manner such that it can pass back theaccumulated web-like material, after the first and the second web-likematerials have been spliced together. In this way, the initial portion,unwound from the second reel and temporarily accumulated by theaccumulator member is carried away to the transformation line andretrieved as dross at the end of the line, for example from the roll orlog containing the splice of the two web-like materials.

In a possible embodiment of the invention, the splicing member and theunwinding members are controlled in a manner such that the splicingmember splices together the first and the second web-like materials whenthe first and the second reel rotate at substantially the sameperipheral speed.

In practice, the accumulator member can include at least one motorizedroll to which the free leading edge of web-like material wound on thenew reel is fixed, so that it can wind around said motorized roll whenthe new reel is made to rotate and before this web-like material isspliced to the web-like material supplied from the reel that is runningout.

In a modified embodiment of the invention, the accumulator memberincludes a suction chamber.

In accordance with another aspect, an object of this invention is toprovide a method of unwinding a web-like material that permits correctcontrol of the web-like material and rapid substitution of empty reelswith new reels without interrupting the feeding of material to aproduction line.

In accordance with the invention, this objects is achieved by a methodcomprising the following phases:

-   -   unwinding a first web-like material from a first reel and supply        said web-like material to a production line,    -   making a second reel rotate and start to unwind a second        web-like material from it,    -   accumulating said second web-like material in an accumulator        member,    -   splicing said second web-like material to said first web-like        material and supply said second web-like material to said        production line.

Further advantageous characteristics and embodiment of the method andthe device in accordance with the invention are indicated in theattached dependent claims.

In the following, the invention will be illustrated with application toan automatic unwinder of new conception, which presents a number ofadvantages and innovations with respect to known unwinders.Nevertheless, it must be understood that the invention could also beapplied to known types of unwinders, for example of the type describedin U.S. Pat. No. 5,906,333, U.S. Pat. No. 6,030,496, EP-A-1,270,470,EP-A-0872440, WO-A-9846509 or to any unwinder device where it ispossible to make two reels rotate simultaneously to perform the splice.The invention can also be applied to unwinders where in regular running,that is after the splice between the web-like materials, the unwindingis effected via traction.

BRIEF DESCRIPTION OF DRAWINGS

The invention will be better understood following the description andthe enclosed drawings, which illustrates a practical, non-limitativeembodiment of the invention. In particular, in the drawings:

FIGS. 1A-1K show side views of the unwinding station in a series ofsuccessive positions during reel changing,

FIG. 2 shows a plan view, partially sectional along II-II of FIG. 1A,with parts removed,

FIG. 3 show a lateral view, partially sectional along III-III of FIG. 4,of the shuttle separately from the unwinding station,

FIG. 4 shows a plan view along IV-IV of FIG. 3,

FIGS. 5A and 5B show a lateral view one of the means of support for thereels in two different positions,

FIG. 6 shows a sectional view along VI-VI of FIG. 5B of one of the meansof support of the reel,

FIGS. 7A and 7B show an enlarged schematic lateral view of the splicingdevice and the accumulator member, in two different positions duringsplicing of the two web-like materials coming from the two reels,

FIGS. 8A and 8B show an enlarged schematic lateral view of a modifiedembodiment for the accumulator member in two different conditions,

FIGS. 9A-9F show four different operating steps of an unwinder deviceaccording to the invention in a different embodiment,

FIG. 10 shows an enlarged detail of the unwinder of FIGS. 9A-9F; and

FIG. 11 shows an enlargement similar to FIG. 10, in a slightly differentembodiment of the splicing means.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

The unwinder device in accordance with the invention, genericallyindicated by reference 1, in the illustrated example includes a loadingstation 3 arranged at the side of an unwinding station 7. A shuttle orcarriage 9 (see FIG. 2 in particular) is provided with reciprocatingtranslatory motion in the directions of the double arrow f9 for movingbetween the loading station 3 and the unwinding station 7. With specificreference to the plan view in FIG. 2, by moving the shuttle 9 to theright it can transfer the reel B2 to the unwinding station 7.

As can be seen in FIGS. 3 and 4 in particular, where the shuttle 9 isshown separately from the other members of the unwinder device, theshuttle has a structure or frame 11 equipped with wheels 10 driven by amotor 12, that provides motion in the directions of the double arrow f9.On the frame 11, support belts 15 with a V-shaped arrangement areprovided to create a support cradle for the reels. Each reel placed onthe shuffle 9 is oriented with its own axis parallel to the direction ofmovement of the shuttle 9 itself. A retainer member is associated withthe support cradle for the free leading edge of every reel each time oneis placed on the shuttle, this member indicated as a whole by reference17 in FIG. 4. The retainer member 17 has a pair of sides rigidly boundto the structure or frame 11 of the carriage or shuttle 9, approximatelyshaped like an inverted V, and indicated by references 19 and 21. As canbe seen in the enlargements of FIGS. 7A and 7B in particular, a bar 23runs between the sides 19 and 21 parallel to the direction of movementof the shuttle 9 and which has an edge destined to facilitate thestraight cutting of the leading edge of the web-like material wound oneach reel placed onboard the trolley or shuttle 9.

The bar 23 is applied close to the lower ends of the respective,substantially vertical arms of the sides 19 and 21. These substantiallyvertical arms are connected at the top to an inclined arm integral withthe frame 11 of the shuttle 9. In the zone of convergence, correspondingto the vertex of the inverted V, the two sides define an empty space forpurposes that will be shortly become clear. A pivot axis 25 passesslightly below the zone of convergence of the two arms forming the sides19 and 21, around which axis a pair of semicircular members 27 and 29associated to each side 19 and 21 rotate. Rollers or rods 31 and 33 areconstrained to each pair of semicircular members 27 or 29. Respectivecylinder-piston actuators 35 and 37 are associated with the sides 19 and21 for controlling the oscillation of the semicircular members 25 and 27for purposes that will become clear in the following.

The vertical arms of the sides 19 and 21 carrying the bar 23 alsosupport a suction roll 24, motorized via a motor 26, the purpose ofwhich will be explained in the following in reference to the principleof operation of the unwinder device.

The unwinding station 7 (see FIG. 1A in particular) includes a pair ofvertical uprights 41 and 43 joined by a horizontal tie beam 45. Insidethis portal-like structure 41, 43 and 45, a space is delimited throughwhich the shuttle 9 transits in its movement of transferring reels fromthe loading stations 3 and 5 to the unwinding station 7. Actually, eachupright 41 and 43 is double, as can be seen in FIG. 2 in particular. Twoarms, indicated as a whole by reference 49, slide vertically on thedouble upright 41, defining a first support for a first reel in theunwinding position in the station 7. The two arms 49 are shownseparately in the enlargement in FIG. 6 and will be described in greaterdetail further on. A similar pair of arms 51 is vertically mobile alongthe double upright 43 and defines a second support for a second reelinside the unwinding station 7. The raising and lowering movement ofeach pair of arms 49 and 51 is driven by respective motors 53 and 55,via horizontal shafts 57 and 59. The shafts 57 and 59 transmit the drivevia angle transmissions and auxiliary shafts, each to a pair of verticalthreaded rods 60 for the arms 49 and 61 for the arms 51 (see FIG. 2 inparticular).

The arms 49 are substantially identical to the arms 51 and thereforeonly the arms 49 will be described in reference to FIG. 6. Each of saidarms has a pair of sides 65 constrained by a cross beam 67 that carriesa nut screw 69 engaged on the respective threaded rod 59. The sides 65are integral with support plates 71 (see FIG. 5A and FIG. 5B) carryingguide rolls 73 along the uprights 41. As can be seen in FIG. 6 inparticular, at the opposite ends of the sides 65 with respect to theposition of the rolls 73, shafts 77 are provided for each arm 49, withhorizontal axes A-A around which the groups 79 oscillate, each of whichcarries a respective spindle or tailstock 81, 83. The spindle-carrier ortail-stock-carrier groups 79 can assume two positions, shown in FIGS. 5Aand 5B. In the position shown in FIG. 5A, the axis of the tailstocks 81and 83, indicated by B-B and parallel to the oscillation axis A-A of thetailstock-carrier groups 79, is above the oscillation axis A-A.Conversely, in FIG. 5B, the axes B-B and A-A are aligned on a horizontalplane. This position is defined by a fixed stop 85 integral with thesides 65 and by a mobile stop 87 integral with the respectivetailstock-carrier group 79. The oscillating movement of thetailstock-carrier groups 79 is controlled by a respectivecylinder-piston actuator 89 carried by each arm 49 (FIGS. 5A and 5B).

As can be seen in the cross section of FIG. 6 in particular, thetailstock 81 is freely mounted on a sleeve 91 sliding inside, thetailstock-carrier 79 and the translatory motion of which along the axisB-B of the tailstock itself is driven by a motor 93 via a rack andpinion transmission 95 and 97. A similar arrangement, indicated with thesame reference numbers, is provided for driving the translatory motionof the sleeve 92 of the tailstock 83 along its own axis. However, to thecontrary of tailstock 81, the tailstock 83 is not idle, but driven inrotation around its own axis by a motor 99 and transmission including afirst belt 101, a pulley 103 on the A-A axis, a second pulley 105, asecond belt 107 and a pulley 109 fitted on the axis of the tailstock 83.

Between the two elements forming the double upright 41, a surfaceunwinding member, indicated as a whole by reference 110, is arranged forthe purpose (as will be described in greater detail further on), ofunwinding the reels of web-like material for a significant part of theunwinding cycle, possibly in combination with the central unwindingmembers associated with the two reel support arms. The surface unwindingmember 110 includes oscillating arms 111 hinged around a horizontal axis113 parallel to the direction of translation of the shuttle 9. Thesurface unwinding member 110 is substantially removed from the view inFIG. 2 for drawing clarity, but is clearly illustrated in FIGS. 1A-1K.The pair of oscillating arms 111 carries three rolls 114, 115 and 116with parallel axes that are also parallel to the axis of oscillation 113of the arms 111, around which belts 117 are run to form the means oftransmission of the unwinding motion to the reels. A guide roll 116,coaxial with the axis of oscillation 113 of the arms 111, is driven inrotation by a belt 119 that is driven by a motor 121. The oscillatorymovement of the arms 111 is imparted by a cylinder-piston actuator 123,while the tension of the belts 117 is controlled by a cylinder-pistonactuator 125 carried by the arms 111, hinged at one end to said arms 111and at the other end to auxiliary arms 112 carrying the transfer roll114 and hinged around an axis of oscillation 112A carried by the arms111. The tensioning of the belts 117 and the movement of the arms 111are controlled using known methods and are not described.

A collection device 131 for empty reels can be moved along the tie beam45, in the directions indicated by the double arrow f131. The collectiondevice 131 has a vertically mobile cradle 133 which can move in thedirections indicated by the double arrow f133 between two end positionsshown in FIGS. 1A and 1B for discharging empty reels onto a conveyor 135or other removal device. The collection device 131 and the respectivecradle 133 also have a horizontal movement up to the position shown inFIG. 1K.

A pair of curved oscillating arms 139 is hinged on the tie beam 45,around an axis 137, parallel to the direction of translation of theshuttle 9. The opposite ends of the arms 139 in correspondence to thosehinged on the tie beam 45, support a roll 141 (possibly motorized)destined to make contact with the web-like material to deviate the paththereof during the phases of changing a reel that has almost run outwith a full reel, as will be described described in further on. Thecurved arms 139 form a loop so as to encircle the axis of a reel that isrunning out.

On the side of unwinding station 7 outputting the web-like material,there is a guide roll 143 (see FIGS. 7A and 7B in particular), to whichthe web-like material unwound from the reel is transferred. The roll 143can be idle or motorized. Along the path of the web-like materialsupplied from the unwinding station, downstream of the guide roll 143, asplicing device is provided, indicated generically and as a whole byreference 151, the function of which is that of splicing a web-likematerial coming from an almost empty reel to the web-like materialcoming from a new reel waiting and destined to substitute the onerunning out. The splicing device 151 includes a counter-pressure roll153 with which rollers 155 and 157 of two respective ply-bonding groups159 and 161 cooperate. The rollers 155 oscillate around an axis 163parallel to the axis of the counter-pressure roll 153 and press againstthe latter under the effect of a pusher member consisting, in thisexample, of pressure bellows 165. The rollers 157 oscillate around anaxis 167 under the force of the pressure bellows 169 or another pushermember. The ply-bonding groups 159 and 161 are known per se and operatein the known manner, and so do not require any additional description inthis context.

An interruption member 171 is arranged above the splicing device 151 forcutting the web-like material coming from the reel that is running outafter splicing with the web-like material coming from a new full reel.In the illustrated example, the interruption device 171 consists of abar 173 carrying a toothed blade 175 and constrained by a pair ofoscillating arms 177. The oscillation of the arms 177 around the axis ofoscillation 179 is controlled by a cylinder-piston actuator 181.

The operation of the unwinder device that has been described up to thismoment will now be illustrated with specific reference to the series ofFIGS. 1A-1K. In FIG. 1A, the support formed by the two parallel arms 51is in a raised position on the double upright 43, which will beindicated as the release position. The tailstock-carrier groups 79associated with the two arms 51 are oriented in a manner such that theaxes B-B of the tailstocks are located above the axis A-A of oscillationof the tailstock-carrier groups themselves. The pair of arms 49 formingthe other reel support is situated in a lowered position on the doubleupright 41.

B1 indicates a first reel from which a first web-like material N1 isunwound for feeding a downstream production line, generically andsummarily indicated by L. The position of the arms 49 is such that thereel being unwound B1 is slightly raised from the shuttle 9, which hasbeen inserted in the space delimited by the uprights 41 and 43 to bringthe reel B1 into the correct position for being grasped and raised bythe arms 49 and by the tailstocks they carry. The surface unwindingmember 110 is kept with its own belts 117 in pressure contact with theexternal surface of the reel B1 and the motor 121, driving the belts 117in rotation, provokes the rotation and thus the unwinding of the reel B1to supply the web-like material N1. The rotation can also be controlledin combination with the central unwinding member associated with thearms 49, i.e. via motor 99. This is particularly advantageous when thereel has a low density.

The collection device 131 is at the extreme left (in the drawing) of thetie beam 45, i.e. on the other side from where the web-like material issupplied to the processing line L. The cradle 133 of the collectiondevice 131 is in the lower position, for releasing an empty reel,indicated by B0, onto the conveyor 135. The latter can be formed, forexample, by a series of rubber wheels or the like.

In FIG. 1B, the axis of reel B1 in the supply phase is still in the sameposition of FIG. 1A, i.e. in the position defined by the axis B-B of thetailstocks 81 and 83 of the support formed by the arms 49. The surfaceunwinding member 110 has rotated in a clockwise direction with respectto the previous figure in order to remain in contact with the reel andto continue to transmit the necessary torque for unwinding it. Thecurved arms 139 have rotated, with respect to the previous figure, in ananticlockwise direction, while the cradle 133 of the collection device131 has been brought to a raised position, directly beneath the tie beam45.

In the unwinding phase illustrated in FIGS. 1A and 1B the torque formaintaining the reel B1 in rotation can be supplied solely by thesurface unwinding member 110, or also in combination with the centralunwinding member constituted by the motorized tail-stock 83. Forexample, in a known manner, torque could be applied via a surfaceunwinding system and also via a central unwinding system, these beingcoordinated to optimize the conditions of unwinding. For particularlysmall and/or particularly compact reels it is also possible to imagineusing directly and exclusively the central unwinding system via thetailstock 83, thereby eliminating the surface unwinding member 110.

Already in this phase, the shuttle 9 that has brought the reel B1 to theunwinding station 7 can be transferred to the loading station 3, toreceive a new reel which shall be inserted in the unwinding station inthe successive cycle. It can thus be appreciated that the shuttle doesnot necessarily have to be a double one, as in traditional machines,although the possibility is not excluded. In the successive figures, theshuttle 9 is always shown in the same position, but it should beunderstood that it could have been removed from the unwinding station.

FIG. 1C shows the start of the phase of exchanging reel B1 that isrunning out with a new reel B2, which must be inserted by the shuttle 9.The insertion takes place with a translational movement of the shuttle 9in the direction orthogonal to the plane of the figure. The surfaceunwinding member 110 has been made to swing in the anticlockwisedirection to move it away from the reel B1. In this phase the reel B1 iskept in rotation only by the motorized tailstock 83, to continuesupplying the web-like material N1 in a substantially continuous mannerto the downstream production line. The pair of arms 49 has started tomove upwards towards the tie beam 45.

In the successive FIG. 1D the pair of arms 49 has reached the positionof maximum lift, also designated as the release position, because inthis position (after the web-like material wound on the reel B1 has runout) the tailstocks 81 and 83 will be extracted from the central axis ofthe empty reel to release it to the collection device 131. The pair ofcurved arms 139 has been rotated to bring it into the angular positionillustrated in FIG. 1A. The distance between the two curved arms 139 isgreater than the width of the web-like material wound on the reel sothat they can be brought close to the axis of the reel itself. In thisposition, all of the space between the uprights 41 and 43 is free andthe shuttle 9 can transit for inserting in this space a new reeldestined to substitute the reel B1 in the phase of running out. In fact,the path of the web-like material N1 from the reel B1 to thetransformation line has been deviated by the action of the oscillatingcurved arms 139, the function of which is exactly that of moving theweb-like material being supplied away from the space in which a new reelmust be inserted.

As can be seen in FIG. 1D, thanks to the fact that the tailstocks 81 and83 of the pair of arms 51 are made to swing in an clockwise directionaround the axis A-A to bring their axes B-B into vertical alignmentabove the axis A-A, the rising motion of the arms 49 does not causecollision between the tailstocks of the two pairs of arms 49 and 51. Thereel B1 does not collide with the tailstocks of the arms 51 as thelatter are in an axially retracted position, i.e. at maximum reciprocaldistance. In this position, the distance between the tailstocks isgreater than the height, i.e. the axial length, of the reels handled bythe unwinder device.

FIG. 1E shows the device in the same condition as the previous figure,but after the translation of the shuttle 9 that has brought a new reel,indicated by B2, between the uprights 41 and 43, and on which a secondweb-like material indicated by N2 is wound. The free leading or headedge of the web-like material N2 has been trimmed and prepared while thereel was in the loading station 5 or 3. As previously mentioned, fortrimming the web-like material a bar 23 is provided that constitutes aguide for the cutting blade or other cutting tool used by the operatorfor creating a clean edge on the web-like material. This edge is thenfixed to the roll 24. As mentioned, this can be a suction roll, forholding the free edge of web-like material. The semicircular members 27and 29 are in the position shown in FIG. 1E in order to support theinitial section of the web-like material above the fixed-axis guide roll143. This permits the shuttle 9 to travel from the loading position tothe unwinding position without the web-like material prepared on itinterfering with the guide roll 143. Once the reel B2 has reached theposition in FIG. 1E, the semicircular members 27 and 29 can be returnedto the retracted position shown in FIG. 7A, so that the web-likematerial N2 rests on the guide roll 143.

In the following FIG. 1F, the pair of aims 51, forming the secondsupport for the reels in the unwinder device has been brought into thelower position on the uprights 43. This position is also called theengagement position, because it is the position in which the reel isengaged by the tailstocks. The tailstock-carrier groups 79 have beenmade to swing in the anticlockwise direction to bring the axes of thetailstocks 81 and 83 associated with the arms 51 into a positionhorizontally aligned with the axis A-A of oscillation of thetail-stock-carrier groups 79. In this condition, the axis B-B of the twotailstocks 81 and 83 carried by the arms 51 is in the same position inwhich the axes of the tailstocks 81 and 83 carried by the arms 49 werein the previous phase of taking the reel B1 from the shuttle 9. Thisallows just a translational movement to be given to the shuttle 9 in thedirection orthogonal to the plane of the figure. Alternatively, ifchanging the geometric set-up of the tailstocks with respect to the arms49 e 51 that carry them were not contemplated, it would be possible toarrange these arms at a reciprocal distance sufficient to avoidcollisions, and give an additional translational movement to the reelinsertion system, for example by equipping the shuttle 9 with a slideproviding a movement orthogonal to the insertion and extractiondirection of the shuttle 9 with respect to the unwinding station 7.

In FIG. 1G the pair of arms 51 has been slightly raised to bring theaxis of the reel B2 into the same position assumed in FIG. 1A by theaxis of reel B1. In this way, as reel B2 has lost contact with thesupport belts 15 provided on the shuttle 9, it is possible to startrotation of the reel B2.

As can be seen in FIG. 1H, at this point the surface unwinding member110 is made to swing in the clockwise direction to bring the belts 117into contact with the outer cylindrical surface of the reel B2; to startthe unwinding of the reel itself. The motor 121 is started with asuitable acceleration ramp and starts to make the reel B2 rotate. It isangularly accelerated until the speed of the web-like material N2 (andthus the peripheral speed of the reel) reaches the feed speed of theweb-like material N1 coming from reel B1. The feed speed of the web-likematerial N1 can be temporarily reduced if appropriate.

The time necessary for bringing the peripheral speed of the second reelB2 up to the peripheral speed of the first reel B1 is relatively short.The web-like material N2 that is supplied by the reel B2 in this phaseis collected around a motorized roll 24 to which the leading edge of theweb-like material has been attached beforehand. To that end, the motor26 is operated, the speed of which is suitably controlled according tothe peripheral speed of the reel B2. Before performing the splicing ofthe web-like material N2 with the web-like material N1, said twomaterials pass through the rollers 155 of the ply-bonding group 159 andthe counter-pressure roll 153, which also serves as a guide and idleroll for the web-like material fed to the downstream production line,before these two elements are pressed against each other.

In the successive FIG. 1I the splicing phase of the web-like material N1coming from the almost empty reel B1 with the web-like material N2coming from the reel B2 is shown. To this end, the ply-bonding groups159 and 161 are operated to bring the respective rollers 155 and 157 topress against the counter-pressure roll 153. The position taken by thesemembers in this phase is illustrated in FIG. 7A. The two series ofply-bonding rollers 155 and 157 splice under pressure the two web-likematerials, which are fed in parallel and at the same speed.

As part of the web-like material N2 was wound around the roll 24 duringthe phase of acceleration of the reel B2, to automatically retrieve thisportion of web-like material, once the above-described splicingoperation has commenced via the closure of the ply-bonding groups it ispossible to slow down and then invert the direction of rotation of themotor 26 and the roll 24 to output the head of the web-like material N2to the transformation line L together with the web-like material N1still in the phase of supply from the reel B1 and the web-like materialN2 being unwound from the reel B2. This situation is shown in detail inFIG. 7B.

At a suitable moment in this phase of operation, the web-like materialN1 coming from the first reel B1 is cut via the interruption member 171.The cutting or interruption phase of web-like material coming from thealmost empty reel B1 is shown in FIG. 1J. After the start of thesplicing operation and up to the passage of the tail of the web-likematerial N1 and the head of the material N2 through the splicing device151, a material formed of three layers is fed from the splicing device151, i.e. the web-like material N1 and the web-like material N2 doubled.After the passage of the head of the web-like material N2 that detachesitself from the roll 24 and the tail of the web-like material N1 throughthe nip formed by the counter-pressure roll 153 and the ply-bondingrollers 157, at the output of the splicing device 151 there will againbe material composed of a single layer only, i.e. the web-like materialN2, that starts the regular feed to the downstream converting line. Thesection in which the splice was formed will be discarded downstream byknown systems and recycled.

In the successive FIG. 1K it is shown how the collection device 131retrieves the empty reel B1 that is released by the tailstocks 81 and 83on the cradle 133. The collection device then moves to a positionsimilar to that in FIG. 1A, with the cradle 133 in the low position fordischarging the residue of the reel B1.

As can be seen comparing FIGS. 1A and 1K, the supply of the web-likematerial N2 continues with the unwinder device in a setup substantiallysymmetrical to that shown in FIG. 1A. When the reel B2 runs out, thedevice will perform a substitution cycle substantially symmetrical tothat described, where the arms 49 and 51, with the respective membersthat they carry, will perform partially inverted operations with respectto that described above.

From the above, it will be appreciated that the above-described unwinderdevice is capable of performing the substitution of an almost empty reelwith a new reel and splicing the web-like material coming from thealmost empty reel with the web-like material coming from the new reelwithout halting supply to the downstream production line and alsoretrieve all of the web-like material unwound from the new reel duringthe splicing phase, for simplifying the recycling operations. Noresidues of web-like material remain on the shuttle 9. The portion ofweb-like material N1 partially unwound from the emptied reel B1 (betweenthis and the interruption device 171), is recovered around the tubularcore of the reel B1 by inverting the direction of rotation of thetailstock 83 of the respective pair of arms 51, such that it cannothamper unloading operations.

As the reel B1 that is running out must be slowed down until it stopsafter the cutting of the web-like material N1 has been performed, thiscontinues to be unwound for a certain length until the direction ofrotation of the reel B1 is inverted to permit its retrieval. To avoidthis residual portion of web-like material N1 interfering with othermembers of the machine, and in particular with the members of thesplicing device, a collection element is advantageously provided, in theform of a curved surface 172 or other system of containment.

The usage of two ply-bonding groups 159 and 161 as described aboveensures that on the portion of material where the splice is made betweenthe web-like materials N1 and N2 there are no free edges that can hamperthe feeding of the material itself. The fact, when the first ply-bondinggroup 159 closes to make the splice, a ply-bonding spliced zone betweenthe two web-like materials N1 and N2 starts to be created. Without thesecond ply-bonding group 161, the portion of web-like materialtemporarily accumulated on the roll 24 would simply be dragged by thematerial after splicing, remaining free with the risk of running astray.The presence of the second ply-bonding group makes sure that thisportion of web-like material N2 is caused to adhere by ply-bonding tothe material that advances in a controlled and not a free manner to thedownstream converting line L. The second ply-bonding group alsoguarantees a more reliable splicing of the layers, exerting sufficienttraction on the portion of material temporarily wound and accumulated onthe roll 24, to facilitate retrieval.

The particular arrangement of the roll 24 for the temporary accumulationof the web-like material N2 coming from the reel B2 downstream of theposition of the first ply-bonding group 159, i.e. of the zone in whichthe web-like materials N1 and N2 are spliced, allows the second reel B2to be accelerated significantly before performing the splicing, and thusessentially of not excessively reducing the feed speed of the web-likematerial. At the same time, contrary to known devices, it is notnecessary to have a large distance between the splicing members and theposition of the reels being unwound. As can be observed in the drawings,the splicing occurs in a position very close to the reels and thispermits better control of the web-like material and greater compactnessof the production line.

From that described above, it is also clear that one of the advantagesof the device in this embodiment is represented by the possibility ofretrieving, without manual intervention, the head of the web-likematerial of the new reel that will substitute the empty reel. Thisrequires the utilization of the motorized roll 26.

However, other configurations are also possible for realizing anaccumulation member for the initial portion of web-like material comingfrom the new reel. An alternative configuration is illustrated in FIGS.8A and 8B. The same or equivalent parts to those of the previous figures(in particular FIGS. 7A and 7B) are indicated with the same referencenumbers. In this case, the roll 24 and the respective motor 26 areabsent and the bar 23 is hollow and equipped with suction slots or holesthat hold the head of the web-like material N2 in the preparation phaseuntil the respective reel B2 is inserted inside the unwinding station 7.

During the acceleration phase of the reel B2, the initial portion ofweb-like material N2 is sucked inside a chamber 200 provided in theunwinding station 7. Thanks to a suction-pipe 202, the pressure insidethe chamber 200 is slightly less than that of the atmosphere. Suctionthrough the hollow bar 23 is interrupted. The web-like material that inthe previous example of embodiment was wound around the roll 24 thusaccumulates in the chamber 200. To avoid the web-like material thataccumulates in the suction chamber 200 from obstructing the suction, abasket 204 is placed inside the chamber to hold the web-like material.

Once the splicing of the two web-like materials is completed, thesuction inside the chamber 200 can be interrupted and all of thematerial that has accumulated is retrieved as shown in FIG. 8B in asimilar manner to that previously described for the material temporarilywound around the roll 24.

With this arrangement, or with that which uses the roll 24, a temporaryaccumulation of web-like material is realized, which will subsequentlybe fed to the production line, and included on the roll containing thesplice between the two layers. This roll is destined, in any case, to berecycled. In this way, the need to remove web-like material dross fromthe unwinding station 7 or the shuttle 9 by hand or with other systemsis avoided.

FIGS. 9A-9F show a simplified unwinder device embodying the invention invarious steps of the splicing phase. FIG. 10 shows an enlargement of thesplicing zone.

The unwinder is provided with two unwinding positions. Referring to FIG.9A, in a first unwinding position a first almost exhausted reel B1 isarranged, from which a first web-like material N1 is fed towards adownstream converting or processing line (not shown). The reel B1 iskept into rotation by a surface unwinding member 301 in the form ofendless belts entrained around rollers 303, 304, 305, 306, 307, roller306 being driven into rotation by a motor (not shown). Roller 303 issupported by a pair of oscillating arms 308 acted upon by acylinder-piston actuator 309, which keeps the belts 301 under tensionwhile the diameter of reel B1 is reduced due to web feeding. The rollers304, 305, 306, 307 are supported by an arm 311 connected to the fixedstructure of the unwinder device. The axis A-A of the reel B1 issupported by arms 302 pivotally connected at C-C to the structure of theunwinder. The arrangement is such that the belts 301 are kept constantlyunder tension and pressed against the outer surface of reel B1, whileits diameter decreases following web paying off, in order to keep thereel into rotation and feed the web-like material N1. The arms 302 arelowered step-wise as the diameter of reel B1 decreases, while betweenone lowering step and the next belt tension is ensured bycylinder-piston actuator 309.

The reel B1 is placed on the pivoting arms 302 by conventional means,not shown.

A second reel B2 of web-like material N2 has been placed in a secondunwinding position, and is supported on axis B-B by pivoting arms 302B.Unwinding belts 301B entrained around rollers or pulleys 304B, 305B,306B, 307B are provided for driving reel B2 into rotation. Similarly toarms 302, also arms 302B can be stepwise lowered while the reel diameterdecreases. A cylinder-piston arrangement 309B connected to anoscillating arm 308B supporting roller 303B keeps the belts undertension and in contact with the outer periphery of reel B2.

In FIG. 9A the reel B2 is not rotating yet, while reel B1 is stilldelivering its web-like material N1. The latter is driven around guidingrollers 311-318 towards the downstream processing line (not shown). ReelB2 is in a waiting position, ready to replace reel B1 once the latter isempty. The front-end portion of the web-like material N2 is arrangedaround guiding roller 314 and its leading edge has been anchored to acore 321B engaged by tailstocks (not shown) which can drive it intorotation around its own axis. The leading edge of the web-like materialN2 is attached to the core 321B e.g. by means of a strip ofpressure-sensitive bi-adhesive tape applied along the edge of theweb-like material. A pressure element 323B is used to press the edge ofthe web-like material N2 against the core 321B. Insertion of the leadingedge of the web-like material N2 towards the core 321B is obtained in amanner known per se, e.g. by means of insertion belts.

A similar symmetrical arrangement 321, 323 is provided for anchoring theleading edge of web-like material N1 on core 321.

A ply-bonding unit 325 is arranged upstream of cores 321, 321B and isused to splice the two web-like materials N1, N2 as required.

Oscillating severing devices 331, 333 and 331B, 333B acted upon byrespective cylinder-piston actuators are arranged between the cores 321,321B and the ply-bonding unit 325 and between the latter and rollers313, 314 respectively. The purpose of these devices will become clearfrom the following description of the splicing cycle.

Starting from the condition shown in FIG. 9A, the device operates asfollows. The reel B1 is almost empty and must be replaced by fresh reelB2. The leading edge of reel B2 has been attached to core 321B.

Before splicing web-like material N1 and web-like material N2 together,the reel B2 is driven into rotation and accelerated until the peripheralspeed thereof reaches the speed of the web-like material N1. In FIG. 9Bboth reels B1 and B2 are rotating. Reel B1 may be slowed down slightlyor may still rotate at normal production speed. The web-like materialpaid-off by reel B2 during this acceleration phase is wound onto core321B, which is kept into rotation and forms an accumulator member.

When the speeds of the two webs N1 and N2 is substantially the same(FIG. 9C), splicing is performed by the ply-bonding unit 325. Thepressure applied on the two webs between the rollers forming theply-bonding unit causes adhesion of the two web-like materials N1 andN2. The leading portion of web-like material N2, which has been woundonto the core 321B, is cut away by severing device 331B (FIG. 9D), whilethe tail edge of the web-like material N1 is separated by severingdevice 333 (FIG. 9E). Once the two severing operations have beenperformed, the reel B1 stops and the processing line downstream theunwinder is fed with web-like material N2 from reel B2 (FIG. 9F).

The core 321B on which the first portion of web-like material N2 hasbeen accumulated is removed. This core can be made of cardboard. In suchcase it is recycled together with the web-like material N2 by returningthem to the pulper. Alternatively, the cores 321, 321B can be made ofplastic, metal or the like. In such case the web-like material woundthereon is removed and recycled, while the core is re-used.

Replacement of reel B2 once it is empty occurs in quite the same way asdescribed above, by accumulating the leading portion of the web-likematerial N1 of a new reel B1 on core 321, splicing and cutting of theleading edge portion by means of the severing device 331 as well ascutting of the tail edge portion of web-like material N2 by means of thesevering device 333B.

Splicing of the two web-like materials N1 and N2 can be performeddifferently than by ply-bonding. E.g., as shown in FIG. 11 (where thesame numbers are used to indicate the same or equivalent parts as inFIGS. 9A-9F, 10), a set of transversely aligned spraying nozzles 340 isarranged across the width of the web-like material. When the two websmust be spliced together, the nozzles 340 spray an adhesive on web-likematerial N2 and the two web-like materials are pressed together byrollers 342, 344. A similar splicing device could be used also in theembodiments disclosed in FIGS. 1-8.

While the above description refers to cores 321, 321B which are removedfrom the machine upon severing the web-like material and the leadingportion of the web-like material wound thereon is recycled, thepossibility is not excluded that the direction of rotation of cores 321,321B be reversed upon splicing, and that at least part of the web-likematerial accumulated thereon be returned and recovered downstream, asdisclosed with respect to the previously disclosed embodiments.

It is understood that the drawings only show possible embodiments of theinvention, which can vary in form and arrangement without howeverdeparting from the scope of the concept underlying the invention. Anyreference numbers in the attached claims are provided only in order tofacilitate the reading of the claims reference being made to theforegoing description and the enclosed drawings, and do not limit thescope of protection of the claims.

1. An unwinder device for unwinding reels of web material comprisingunwinding members for simultaneously unwinding a first reel and a secondreel, a splicing device for splicing together a first web materialcoming from said first reel and a second web material coming from saidsecond reel, said splicing device comprising two co-acting opposingsplicing members, at least one accumulator member for accumulating saidsecond web material supplied by said second reel before splicing to thefirst web material supplied by said first reel, wherein said accumulatormember is placed, along a path of the second web material, downstream ofsaid splicing device and downstream of a zone in which said splicingbetween said first web material and said second web material starts. 2.The unwinder device according to claim 1, wherein said accumulatormember, said splicing device and said unwinding members are arranged andcontrolled such that while unwinding said first web material from saidfirst reel and supplying said first web material to a production line,said second reel is put into rotation and starts to unwind said secondweb material; and said second web material is accumulated in anaccumulation zone before said splicing; after said splicing said secondweb material is fed to said production line.
 3. An unwinder deviceaccording to claim 1, wherein said splicing member and said unwindingmembers are controlled in a manner such that the splicing member splicestogether the first web material and the second web material when saidfirst reel and said second reel rotate at substantially a commonperipheral speed.
 4. The unwinder device according to claim 1, whereinsaid accumulator member includes at least one roll to which a freeleading edge of said second web material is anchored, the second webmaterial winding itself around said roll when the second reel is made torotate and before the second web material is spliced to the first webmaterial.
 5. The unwinder device according to claim 4, wherein said rollis motorized.
 6. The unwinder device according to claim 4, wherein saidroll is a suction roll for holding the free leading edge of the secondweb material.
 7. The unwinder device according to claim 1, wherein saidaccumulator member is situated in a fixed position.
 8. The unwinderdevice according to claim 1, wherein said splicing device is aply-bonding device.
 9. The unwinder device according to claim 8, whereinsaid splicing device includes two ply-bonding groups.
 10. The unwinderdevice according to claim 1, wherein said splicing device has twosplicing zones arranged in series along the path of the second webmaterial.
 11. The unwinder device according to claim 1 furthercomprising severing devices for interrupting spliced web material comingfrom a reel that is running out after splicing with the first webmaterial and the second web material coming from a new full reel. 12.The unwinder device according to claim 1, wherein said at least oneaccumulator member is constructed and arranged to retain said second webmaterial accumulated and remaining thereon after said splicing.
 13. Theunwinder device according to claim 12 further comprising severingdevices for severing the second web material accumulated on saidaccumulator member.
 14. An unwinder device for unwinding reels of webmaterial comprising unwinding members for simultaneously unwinding afirst reel and a second reel, a splicing device for splicing together afirst web material coming from said first reel and a second web materialcoming from said second reel, at least one accumulator member foraccumulating said second web material supplied by said second reelbefore splicing to the first web material supplied by said first reel,wherein said accumulator member is placed, along a path of the secondweb material, downstream of a zone in which said splicing between saidfirst web material and said second web material starts, and wherein saidaccumulator member is reversible and passes back accumulated webmaterial, after the first web material and the second web material arespliced together.
 15. An unwinder device for unwinding reels of webmaterial comprising unwinding members for simultaneously unwinding afirst reel and a second reel, a splicing device for splicing together afirst web material coming from said first reel and a second web materialcoming from said second reel, at least one accumulator member foraccumulating said second web material supplied by said second reelbefore splicing to the first web material supplied by said first reel,wherein said accumulator member is placed, along a path of the secondweb material, downstream of a zone in which said splicing between saidfirst web material and said second web material starts, and furthercomprising a shuttle mobile between at least one loading station and anunwinding station for transferring reels from said loading station tosaid unwinding station, and wherein said accumulator member is carriedby said shuttle.
 16. The unwinder device according to claim 15, whereinsaid shuttle includes retaining devices for a free leading edge of thefirst web material and the second web material wound on the first reeland the second reel respectively carried by said shuttle.
 17. Theunwinder device according to claim 16, wherein said retaining devicesare associated with a motorized roll.
 18. A method for unwinding reelsof web material comprising unwinding a first web material from a firstreel and supplying said first web material to a production line, makinga second reel rotate and starting to unwind a second web material fromsaid second reel; accumulating said second web material in anaccumulation zone before splicing, splicing by two opposing andco-acting splicing members said second web material to said first webmaterial and supplying said second web material to said production line,wherein said second web material is accumulated in said accumulationzone, before the splicing, by an accumulator member arranged downstreamof said splicing members.
 19. The method according to claim 18, whereinsaid first reel and said second reel are made to rotate at substantiallya common peripheral speed before splicing said first web material tosaid second web material.
 20. The method according to claim 18, whereinsaid second web material is temporarily wound around a roll.
 21. Themethod according to claim 18, wherein said accumulation zone is situateddownstream, along a path of the second web material, with respect to azone where the splicing between the first web material and the secondweb material starts.
 22. The method according to claim 18, wherein saidfirst web material and said second web material are spliced together byply-bonding.
 23. The method according to claim 18, wherein said firstweb material and said second web material are spliced together via twodistinct splicing groups arranged in series along a feed path.
 24. Themethod according to claim 23, wherein said accumulation zone is arrangedbetween said first splicing group and said second splicing group. 25.The method according to claim 18, wherein the second web materialaccumulated in said accumulation zone is separated from the first webmaterial coming from a respective reel and recycled.
 26. A method forunwinding reels of web material comprising unwinding a first webmaterial from a first reel and supplying said first web material to aproduction line, making a second reel rotate and starting to unwind asecond web material from said second reel; accumulating said second webmaterial in an accumulation zone before splicing, splicing said secondweb material to said first web material and supplying said second webmaterial to said production line, wherein said second web material isaccumulated in said accumulation zone before splicing, said accumulationzone being arranged downstream of a zone in which said splicing starts,and wherein after the splicing of said second web material to said firstweb material, the spliced web material accumulated in said accumulationzone is retrieved and fed to said production line.
 27. A method forunwinding reels of web material comprising unwinding a first webmaterial from a first reel and supplying said first web material to aproduction line, making a second reel rotate and starting to unwind asecond web material from said second reel; accumulating said second webmaterial in an accumulation zone before splicing, splicing said secondweb material to said first web material and supplying said second webmaterial to said production line, wherein said second web material isaccumulated in said accumulation zone before splicing, said accumulationzone being arranged downstream of a zone in which said splicing starts,wherein said second web material is temporarily wound around a roll, andwherein said roll is made to rotate in a winding sense for temporarilyaccumulating said second web material and, after the splicing of thefirst web material and the second web material, direction of rotation ofsaid roll is inverted.
 28. A method for unwinding reels of web materialcomprising unwinding a first web material from a first reel andsupplying said first web material to a production line, making a secondreel rotate and starting to unwind a second web material from saidsecond reel; accumulating said second web material in an accumulationzone before splicing, splicing said second web material to said firstweb material and supplying said second web material to said productionline, wherein said second web material is accumulated in saidaccumulation zone before splicing, said accumulation zone being arrangeddownstream of a zone in which said splicing starts, wherein said secondweb material is temporarily wound around a roll, and wherein a portionof the second web material temporarily accumulated in said zone is madeto adhere to the first web-like material when said second web materialis retrieved.
 29. An unwinder device for unwinding reels of web materialcomprising unwinding members for simultaneously unwinding a first reeland a second reel, a splicing device for splicing together a first webmaterial coming from said first reel and a second web material comingfrom said second reel, at least one accumulator member for accumulatingsaid second web material supplied by said second reel before splicing tothe first web material supplied by said first reel, wherein saidaccumulator member is placed, along a path of the second web material,downstream of a zone in which said splicing between said first webmaterial and said second web material starts, and wherein saidaccumulator member is constructed and arranged to retain accumulated webafter said splicing.
 30. A method for unwinding reels of web materialcomprising unwinding a first web material from a first reel andsupplying said first web material to a production line, making a secondreel rotate and starting to unwind a second web material from saidsecond reel; accumulating said second web material in an accumulationzone before splicing, splicing said second web material to said firstweb material and supplying said second web material to said productionline, wherein said second web material is accumulated in saidaccumulation zone before splicing, said accumulation zone being arrangeddownstream of a zone in which said splicing starts, and whereinaccumulated web material is retained, after said splicing, in saidaccumulation zone.